(a) Field of the Invention
The present invention relates to a flexible roll forming device. More particularly, the present invention relates to a flexible roll forming device for subjecting a blank material to roll forming of a formed beam having different widths and heights along a length direction.
(b) Description of the Related Art
In general, roll forming is a method including uncoiling a material coil and passing it through multi-stages of roll forming units each having one pair of an upper roll and a lower roll disposed on a line for forming a predetermined shape by successive bending. Further, the roll forming method is applicable to fabrication of straight-type formed products formed by bending into predetermined shapes, such as vehicle bumper beams or other members of a certain shape.
FIG. 1 illustrates a schematic view of a related art roll forming system with process steps thereof shown therein.
Referring to FIG. 1, in the related art roll forming method, an uncoiler 1, provided at a start of a process line for uncoiling a coil 10 supplied thereto, processes an uncoiling step S1 of feeding the coil.
A straightener 2 is provided next in a process direction after the uncoiler 1, to process a straightening step S2 for straightening the uncoiled coil 10 from the uncoiler 1 to be flat.
A press 3 is provided next in the process direction after the straightener 2, to process a piercing step S3 for forming holes for various purposes in the coil 10 fed from the straightener 2.
Roll forming units RU1-RU10 of about 10 stages are disposed next in the process direction of the press 3, to process a roll forming step S4 for successively bending the coil 10 being fed thereto through the uncoiler 1, the straightener 2, and the press 3 for roll forming a predetermined straight type of formed beam 20.
A cutting press 4 is provided next in the process direction after the roll forming units, to process a cutting step S5 for cutting the formed beam 20 to produce a formed product 30.
However, in view of the nature of the roll forming with the related art roll forming units, it has a drawback in that only formation of beams having a fixed cross-section along the length direction of the beams is possible, and formation of beams having different widths and heights along the length direction thereof is not possible.
Consequently, since formation of products of different modified cross-sections having different widths and heights along the length direction cannot be formed with the roll forming method, the products have been formed by applying multi-stage forming with a non-continuous process and long cycle time.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.